This invention relates to multiple photoflash lamp devices and, more particularly, to an improved reflector system for linear arrays of photoflash lamps.
Multiple photoflash lamp arrays with lamp-reflector units in linear rows facing in opposite directions are well known in the art as disclosed, for example, in U.S. Pat. Nos. 3,598,984, Slomski, and 3,725,693, Anderson et al. The lamp-reflector units in such linear photoflash lamp arrays are generally arranged in two parallel rows with the lamp and reflectors of one row staggered relative to the lamps and reflectors of the other row, and with the reflectors of one row preferably nested back to back with the reflectors of the other row in order to provide a compact package. In the more general description of Slomski, each row of reflectors preferably is formed of a separate strip of material with an insulation means between the rows of reflectors to minimize distortion of adjacent reflectors upon flashing of a lamp. The insulation means can comprise a sheet of suitable material, such as asbestos, or it can comprise a thermal barrier such as an air space.
The Anderson et al. patent is directed to the mechanical details of the nested reflector arrangement; it describes a pair of plastic molding reflector panels (e.g. injection molded panels) arranged in nested back-to-back relation, and stand-off shoulder means, (e.g. pins and sockets or ribs) located on the back sides of the reflector panels and interfitting or abutting one another to locate the two opposed reflector panels in a predetermined back-to-back relation with their nested reflectors spaced a predetermined distance apart. This structure forms a relatively rigid system that is quite heat resistant to the photoflash lamps, which radiate a considerable amount of heat during flashing. The design of the system is good, but injection molded parts are expensive, subject to warpage and breakage through shipping, and require a considerable amount of individual handling to achieve a finished assembly.
Other prior art multiple flash products, such as the flashcube described in U.S. Pat. No. 3,358,131, have used vacuum-formed reflector strips made from relatively thin film (e.g., 7.5 mil) plastics which have been aluminized. This system lends itself to automatic fabrication of many reflectors from sheets of clean material, thereby eliminating a significant portion of the individual handling and costs associated with injection molded parts. Further the thin vacuum-formed reflectors result in a significant weight reduction in the plastic material used, as the average wall thickness of the injection molded reflector strip is about 20 mils. When the thin-walled, vacuum-formed reflector strips were tested in the aforementioned two-sided linear arrays, however, it was found that some type of heat shield was required between the nested strips to prevent heat distortion of adjacent reflectors from the hot flashed lamps. It was also noted that the thin reflector strips could shift within the flash array package and thereby misalign the position and shape of the reflectors.